Devices in motor vehicles that increase driving comfort and safety are known. For example, in connection with the starter release, numerous checks and safety inquiries have been proposed. DE 197 32 924 A1 proposes a plurality of combinations of states of driving state magnitudes that either result in a starter release or that forbid a starter release. The gear position, for example, is such a driving state magnitude. In this connection, one can especially detect whether the neutral position is engaged. Additional driving state magnitudes can be derived from a motor vehicle brake or a torque transmission system. Interrogating switching intention signals can also be included in the evaluation as to whether a starter release is allowed or is not included. When certain states of one or several driving state magnitudes are present, then one can bring about automated actions so that, subsequently, one can ensure a reliable starter release. If, for example, one detects that a neutral position has not been set, then a brake is actuated in an automated fashion and the torque transmission system is disengaged in an automated fashion, and only then is a starter release issued to get the engine started.
DE 199 00 820 A1 presents a servo support device that actuates a starter for the purpose of starting an internal combustion engine only when the neutral position has been set or when a clutch has been completely disengaged.
DE 103 20 280 A1 presents a process and a device for operating an automatic or automated gear with parking brake or rollaway safety. A process for releasing a starting process in a vehicle equipped with an automated gearbox reveals the following process steps: First, one checks to see whether an ignition has been turned on and the engine is turned off and the brake is actuated. If this is the case, one checks to see whether the clutch has been disengaged. If yes, the starter operation is released. The following process steps are proposed in case of a vehicle with an automated gearbox with parking brake: First, one checks to see whether the ignition is on and the parking brake is engaged. The starter is activated if the driver wishes to start the engine up. The disengagement of both clutches is checked in a dual-clutch gear.
In the case of dual-clutch gears, for safety reasons, one advantageously cannot use the self-locking clutch actuator sets, which, due to spring devices, run currentless into the state “clutch open.” This property of a clutch is also referred to as “normally open” or “forcibly open”. In dual-clutch gears, this type of clutch is therefore suitable in a preferred manner because, as both clutches are closed, serious damage can be done in the gear and on the clutches when two different transmission ratios act upon one and the same power takeoff shaft. This is why, in the case of dual-clutch gears, there is a basic rule to the effect that both clutches must be opened in situations that are critical in terms of safety. In the case of automated gearboxes or manual gearboxes, on the other hand, one basically applies the concept of not changing the clutch setting in situations that are critical in terms of safety. This is why vehicles with only one clutch are mostly equipped with the self-locking clutch type, which is closed in its basic state. This is also referred to as “normally closed” or “forcibly closed”.
The distance measurements that are required in this connection are performed by a sensor. This can be done by a path or travel sensor directly as an absolute path measurement, incremental path measurement or differential path measurement on the crankshaft. In case of a brushless EC engine that drives the clutch actuator set, for example, one can also perform the incremental path measurement so that, assuming a typical length of 20 mm of the total path of the actuator set, for example, one can attain a referencing accuracy of 0.2 mm, in other words, one percent of the total path.
If the clutch actuator set is moved into a predetermined position and if it is left there for a period of time, then one talks in terms of “parking” the clutch in that position.
To start the vehicle or to turn it off, one uses an initialization device, which, for example, can be designed in the form of an ignition lock with ignition key or also in the form of a button or switch with a card. By turning the ignition key or by pressing the button, the driver can start operating the vehicle before every run or he can turn it off at the end of each run.